文章目录
- 1 要在Linux主机上做
- 2 git
- 3 注意事项
- 报告
- Task 1
1 要在Linux主机上做
完成的功能主要是利用Java储存数据以及查询数据。
Apache Derby relational database that you create
mongodb
Task 1 Heap file implementation: 40/100
Task 2 Range query implementation: 30/100
Task 3 Derby database and queries: 15/100
Task 4 MongoDB database and queries: 15/100
2 git
名字和邮箱
you with your full name as per course enrolment and your student email address.
git config --global user.name ""
git config --global user.email "@qq.com"
git config --global --list
git log
3 注意事项
data:https://canvas.rmit.edu.au/courses/90603/assignments/679757
Derby 和 MongoDB必须每次注意打开和关闭
第四周要演练Java的代码，所以一定要懂！
报告
要解释代码的每一步
Task 1
主要任务就是把这个csv文件储存到heap文件中。
数据库中的每一列是可变长度的，咱们可以用固定长度来实现。不过为了节省储存空间。建议使用变长的空间。
Int --> 4bytes
heap file是一个二进制的文件，头需要记录每一页的record有多少行，页与页之间可能 有gap。
java dbload -p pagesize datafile
输出名字是heap.pagesize，二进制是用堆实现的。page的大小呢，可以是1024,2048,或者4096。
程序每次把一个页写到磁盘中，包括花多少豪秒，这个页有多少record，可以使用xxd测试这个输出。
解释如何生成这个heap file。
xxd heap.pagesize | less
Database Systems
COSC 2406/2407
Assignment 1
Assessment
Type
Individual assignment. Submit online via Canvas→Assignments→Assignment 1. Marks awarded
for meeting requirements as closely as possible. Clarifications/updates may be made via
announcements/relevant discussion forums.
Due Date
Week 6, Tuesday 5 April 2022, 11:59pm
Marks
100 points (20% of the overall assessment)
- Overview
You will use the AWS Linux instance assigned to you and the data from a public source to complete the following tasks: - implement in Java a heap file to store the data;
- implement in Java a query on the data;
- store and query the data in an Apache Derby relational database that you create, and
- store and query the data in a MongoDB database that you create.
In the second assignment, you will extend your solution developed in this assignment and conduct further timing
experiments on your AWS Linux instance with indexes. - Learning Outcomes
This assessment relates to the following learning outcomes of the course:
•
CLO 1: Explain and critique data structures and algorithms used to efficiently store and retrieve information in
database systems,
•
CLO 2: Evaluate, critically analyse and compare alternative designs for implementation of database systems,
including data models, file structures, index schemes, and query eval（such as file
structures and index schemes) according to analysis of requirements and specified constraints. - Submission
When you submit work electronically, you agree to the assessment declaration:
https://www.rmit.edu.au/students/student-essentials/assessment-and-exams/assessment/assessment-declarationSubmit on Canvas: Assignments > Assignment 1. You MUST submit:
•
a zip file of your code for tasks 1 and 2 (all Java sources files including your git log); and
•
your report (a single PDF file) that explains your approach and answers for each task (1, 2, 3 and 4), including
description of any scripts for data pre-processing, queries you used, and output.
Progress submission of your Java code in Week 4 You must make a progress submission of your Java code and your git
log.
Failing
to
do
this
result
in
a
penalty
of
10
points.
Progress submission due date: Week 4, Thursday 24 March 2022, 23:59.
Late submission:
•
After the due time, you will have 724 hours to submit your assignment as a late submission. Late submissions
follow the same procedure but will be penalised by 10 points for each (up to) 24 hours being late. For
assignments that are more than 724 hours late, zero points will be awarded.
•
Tasks (Section 4) in this assignment require you run database systems and timing experiments in a cloud(AWS)
Linux instance. All experiments and database systems must be shut down before you log out of your Linux
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instance. Otherwise your instance may run out of memory. Other precautions are provided via
announcements on Canvas. Ignoring such precautions will NOT be grounds for extension to due time.
Page 3 of 6 - Academic integrity and plagiarism (standard warning)
Academic integrity is about honest presentation of your academic work. It means acknowledging the work of others while
developing your own insights, knowledge and ideas. You should take extreme care that you have:
•
Acknowledged words, data, diagrams, models, frameworks and/or ideas of others you have quoted (i.e. directly
copied), summarised, paraphrased, discussed or mentioned in your assessment through the appropriate
referencing methods,
•
Provided a reference list of the publication details so your reader can locate the source if necessary. This includes
material taken from Internet sites.
If you do not acknowledge the sources of your material, you may be accused of plagiarism because you have passed off
the work and ideas of another person without appropriate referencing, as if they were your own.
RMIT University treats plagiarism as a very serious offence constituting misconduct. Plagiarism covers a variety of
inappropriate behaviours, including:
•
Failure to properly document a source
•
Copyright material from the internet or databases
•
Collusion between students
For further information on our policies and procedures, please refer to https://www.rmit.edu.au/students/student-
essentials/rights-and-responsibilities/academic-integrity - Marking Guidelines
Task 1 Heap file implementation: 40/100
Task 2 Range query implementation: 30/100
Task 3 Derby database and queries: 15/100
Task 4 MongoDB database and queries: 15/100
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Assessment details
Data: The data that you are going to use in this assignment is available from:
https://canvas.rmit.edu.au/courses/90603/assignments/679757and you can download the file on another machine and use scp to copy to your AWS Linux instance (you may need to
temporarily store files in the temp directory on titan if you are doing this outside of RMIT).
The first four lines are not data but headers for you to create and name fields in the databases for Tasks 3 and 4.
Run database systems and timing experiments
Timing experiments are only reliable when running one program at a time. You should only run one database system,
Derby or MongoDB, at a time and shut down one database system before starting the other. All database systems must
be shut down before you run your own program and before you log out of your Linux instance. Otherwise, your instance
may run out of memory. Other precautions are provided via announcements on Canvas. Ignoring such precautions will
NOT be grounds for extension to due time.
Walkthrough of your Java code in Week 4 You must undertake a walk-through during a scheduled lab class in week 4
explaining your Java code for Task 1 and answer questions about it. Failing to do this will result in a penalty of 10 points.
Code and git log: You must use git to track your assignment code. You need to set up your git repository so that each
commit identifies you with your full name as per course enrolment and your student email address. It sets an expectation
of professionalism. You must submit a text file of your git log. Do not include the git repository in your code submission.
Report: Create a file called report.pdf (various software including Word processors can export as PDF). Use this file to
report on the following four tasks. Each task should be reported under a separate heading with the task name and
description, for example for the first task use the heading: Task 1: Derby. Limit your report to three pages.
•
Description of scripts for data preprocessing for loading MongoDB and Derby databases, rather than the scripts
themselves, should be included in the report. Scripts are submitted with your code in the zip file to enable markers
to test your scripts.
•
Description of query output, rather than a long list of output, should be included in the report.
Task 1: Implement a Heap File in Java (40 points)
You are ONLY going to use the following 11 fields of the source dataset (field names are in first line of the file, with the
exception of personName, the second column, which is called rdf-schema#label):
personName STRING
birthDate DATE
birthPlace label STRING
deathDate DATE
field label STRING
genre label STRING
instrument label STRING
nationality label STRING
thumbnail STRING
wikiPageID INTEGER
description STRING
Write a program in Java to store and organise the data in a heap file using Java on your AWS Linux instance.
The source records are variable-length. Your heap file may hold fixed-length records (you will need to choose appropriate
maximum lengths for each field). However, you may choose to implement variable lengths for some fields, especially if
you run out of disk storage space or RAM.
All attributes with Int type must be stored in 4 bytes of binary, e.g. if the value of ID is equal to 70, it must be stored as
70 (in decimal) or 46 (in hexadecimal; in Java: 0x46). It must not be stored as the string “70”, occupying two bytes. Your
heap file is therefore a binary file. For simplicity, the heap file does not need a header (containing things like the number
of records in the file or a free space list), though you might need to keep a count of records in each page. The file should
be packed, i.e. there is no gap between records, but there may be gaps at the end of each page.
The executable name of your program to build a heap file must be dbload and should be executed using the command:
java dbload -p pagesize datafile
The output file will be heap.pagesize where your converted binary data is written as a heap. Where ‘pagesize’ means
the actual page size in bytes, eg: 1024, 2048, 4096, etc.
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Your program should write out one “page” of the file at a time. For example, with a pagesize of 4096, you would write
out a page of 4096 bytes possibly containing multiple records of data to disk at a time. You are not required to implement
spanning of records across multiple pages. Your dbload program must also output the following to stdout, the
number of records loaded, number of pages used and the number of milliseconds to create the heap file. You are also
suggested the use of utilities like xxd for examining the output heap file to see if their code is producing the expected
format:
xxd heap.pagesize | less
In your report, explain how your code implements a heap file. Give detailed instructions to test your heap file and show
that it includes all records from the data source.
Task 2. Implement a range query on your heap file (30 points).
Write a program to perform range query search operations on the field “birthDate” heap file (without an index) produced
by your dbload program in Task 1. Your program must be named birthDate with two date values as input. For example
for the query “List all artists born in 1970”. The command below execute this query, where the integer 19700101 is for
the date “1st January 1970”:
java birthDate 19700101 19701230
Your program should read in the file, one “page” at a time. For example, if the pagesize parameter is 4096, your program
should read in the first records from disk. These can then be scanned, in-memory, for a match. If a match is found, print
the matching record to stdout, there may be multiple answers. If no match is found, read in the next pagesize records of
the file. The process should continue until there are no more records in the file to process. In addition, the program must
always output the total time taken to do all the search operations in milliseconds to stdout.
In your report, explain how your code implements the range query, provide the query, a description of returned results
and timings Give instructions to test your program.
Task 3: Derby database and queries (15 points)
You are required to load the data into Derby. In your report:
•
Explain how have you chosen to structure the Derby relational database and give reasons.
•
Provide details of the time to load the data into Derby. You need to analyse the data and consider appropriate
ways to structure the data and then using any scripting, programming or other tools to format the data
accordingly.
•
In your report you are expected to provide reasoning for the way you have structured the data in each database.
•
Postgraduate students only: What alternative way or ways could you have organised the data when storing in
Derby, and what advantages or disadvantages would these alternative designs have?
Undertake the following queries (include timings when you run the queries). Run each query twice and compare the
times (first after rebooting the machine and then again after the query has already been run once).
•
How many artists are in the movement known as Post-Impressionism?
•
Which punk rock musicians were born in Australia?
In your report provide the queries, description of answers returned by Derby and timings. Explain differences in timings.
Task 4: MongoDB database and queries (15 points)
You are required to load the data into MongoDB. In your report:
•
Explain how you have chosen to structure the data inserted in MongoDB.
•
Provide details of the time taken to load the data (mongoimport is one utility that will provide such information).
A naive import into a flat structure in Mongodb will not accrue you a great mark. You need to analyse the data
and consider appropriate ways to structure the data and then use any scripting, programming or other tools to
format the data accordingly.
•
Postgraduate students only: What alternative way or ways could you have organised the data when storing in
MongoDB, and what advantages or disadvantages would these alternative designs have?
Undertake the following queries (include timings when you run the queries). Run each query twice and compare the
times (first after rebooting the machine and then again after the query has already been run once).
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•
How many artists are in the movement known as Post-Impressionism?
•
Which punk rock musicians were born in Australia?
In your report provide the queries, details of the answers returned by MongoDB and query timings. Explain differences
in timings.
